The offline tour map is scaled to online maps and offers more detailed information than the online maps, along with the offline map bring you a peace of mind when you know where you are when internet is not available and you are in/outside the Natchez Trace parks!
You can search & plot on maps the points of attractions along the parkway to decide how far they are from your location.
The tour guide tells you more about the parkway and the points of attractions along the parkway.
You can do lots more with the app such as recording then sharing your trips as named trails with friends, displaying your friends locations, contact sharing, note keeping, timer, fitness etc.
The large app file size is due to the embedded offline tiles that you don’t have to download yourself.